Harvesting them in threes nets about 160x3 = 480 ADAM
Saving them in threes nets about 80x3 = 240 + 200 Bonus = 440 ADAM + Achievement for saving them all.
Aside from that, the "Hypnotize Big Daddy" plasmid is awesome, Big Daddy on Big Daddy fights for the win!
I saved them, at first to get the achievement, then because I felt a little bad for them. Even though I already beat the hell out of it, I want to own it...just because it's that awesome.